Tumor selective E1a and E1b mutants

Abstract

Modified E1a regulatory sequences are provided, wherein at least one Pea3 binding site, or a functional portion thereof, is deleted. Also provided are modified E1a sequences that selectively express particular isoforms. Also provided is an E1b-19K clone insertion site. These modified sequences can be used individually, or in combination with one another, to provide tumor-selective expression of proteins.

What is claimed is: 
     
       1. A recombinant adenovirus-comprising:
 (i) a DNA sequence inserted into an E1b-19K insertion site, wherein the insertion site is located between the start site of E1b-19K and the start site of E1b-55K; and 
 (ii) a modified E1a regulatory sequence, wherein at least one Pea3 binding site, or a functional portion thereof, is deleted. 
 
     
     
       2. The recombinant adenovirus of  claim 1 , wherein the insertion site comprises a deletion of 202 base pairs following the start site of E1b-19K. 
     
     
       3. The recombinant adenovirus of any one of  claims 1  or  2 , wherein the DNA sequence is a sequence encoding tumor necrosis factor, or a functional portion thereof. 
     
     
       4. The recombinant adenovirus of any one of  claims 1  or  2 , wherein the DNA sequence is a sequence encoding kras, or a functional portion thereof. 
     
     
       5. The recombinant adenovirus of  claim 1 , wherein at least one nucleotide in the range of −305 to −141 of said E1a regulatory sequence is retained. 
     
     
       6. The recombinant adenovirus of  claim 1 , wherein at least one of Pea3 II, Pea3 III, Pea3 IV, and Pea3 V, or a functional portion thereof, is deleted. 
     
     
       7. The recombinant adenovirus of  claim 1 , comprising the nucleic acid sequence of vector dl309-6, TAV-255, dl55, dl200, dl230, or dl200+230. 
     
     
       8. The recombinant adenovirus of  claim 7 , comprising the nucleic acid sequence of vector TAV-255. 
     
     
       9. The recombinant adenovirus of  claim 1 , wherein said recombinant virus selectively expresses an E1a isoform, wherein the sequence encoding the E1a isoform is operably linked to said modified E1a regulatory sequence. 
     
     
       10. The recombinant adenovirus of  claim 9 , wherein the virus selectively expresses E1a-12S. 
     
     
       11. The recombinant adenovirus of  claim 9 , wherein the virus selectively expresses E1a-13S. 
     
     
       12. The recombinant adenovirus of  claim 1 , wherein said recombinant virus substantially excludes expression of an E1a isoform, wherein the sequence encoding the E1a isoform is operably linked to said modified E1a regulatory sequence. 
     
     
       13. The recombinant adenovirus of  claim 12 , wherein the excluded E1a isoform is E1a-12S or E1a-13S.